In the prelude to optional part of the Week 1 exercise (on implementing backprop for CNNs), it’s stated:
When in an earlier course you implemented a simple (fully connected) neural network, you used backpropagation to compute the derivatives with respect to the cost to update the parameters. Similarly, in convolutional neural networks you can calculate the derivatives with respect to the cost in order to update the parameters.
[Emphasis mine.]
Shouldn’t it be “derivates of the cost with respect to the parameters” instead? (e.g. \frac{\partial{J}}{\partial{w}})